Claude Fable vs GPT Astra
The top of the market, and the two land within 48 hours of each other: Fable 5.1 on 1 September 2026, GPT-6 Astra on the 3rd. They also cost the same, $10 per million input tokens and $50 per million output. Astra is the stronger operator, state of the art on computer use and built for work that spans applications. Fable 5.1 is the stronger reasoner and the cheaper one to run repeatedly, because its cache reads bill at 2.5% of the input price. Pick by whether the job is thinking or doing.
| Claude Fable | GPT Astra | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Current release | Fable 5.1 | GPT-6 Astra |
| Tier | Frontier | Frontier |
| Context | 1M | 1M |
| Cost | Frontier price | Frontier price |
| Modalities | text, vision | text, vision |
| Open weights | No | No |
Cost is a tier, not a quote, providers change prices often. Check Anthropic and OpenAI before you commit. Last updated 2026-09-04.
Which one to pick
Demanding reasoning and long-horizon agentic work, when Opus at high effort still falls short
Reach for it when- Deep reasoning and research where the answer matters more than the click path
- Long agent runs over a large repeated context, where caching dominates the bill
- You want a model available on AWS, Google Cloud and Azure from day one
The hardest end-to-end work, computer use, and long agentic runs that span applications
Reach for it when- Driving real interfaces, spreadsheets, forms and browsers end to end
- Work that spans several applications rather than one codebase
- You are already building on OpenAI tooling
Related comparisons
- Claude Opus vs GPT AstraThe practical version of the frontier question, because Opus 5 costs half what Astra does, $5 and $25 per million tokens against $10 and $50, and Anthropic recommends it as the default for most workloads.
- GPT Astra vs GPT SolThe within-OpenAI upgrade question.
- GPT Astra vs Gemini ProA five-fold price gap between two frontier models.
- Claude Fable vs Claude OpusThe within-Claude question.